have a refurbished unit installed. My 400E is "clicking" in reverse and engaged slowly..very slowly. My tech has told me it's a matter of time before the reverse goes out. His recommendation is have a remanufactured tranny installed. The cost of that after the core charge is close to the R&R labor, parts and repair of the existing tranny and that only gets you the new clutch packs and a reseal....There are several reman shops that offer the trannies with a full 2 year warranty...good deal... talk to your tech.

__________________
Jeff
'87 300E
'92 400E
'06 ML350